Calculation of earth resistance for a deep-driven rod in a multi-layer earth structure

In order to obtain an equation for calculating the earth resistance of a deep-driven rod in a horizontally stratified multilayer earth, expressions for the potential in such a structure are derived and evaluated with reference to previously established expressions for the two-layer model. In addition, when a series of numerical test data (earth parameters) is applied to the obtained equation, the behavior of earth resistance for a deep-driven rod in regard to the multilayer problem is revealed through examination of the calculations. The eventual purposes of the derived equation is to help the grounding designer obtain the earth resistance required by making it possible to more accurately estimate the depth of boring or the length of a rod even in a multilayer situation